summaryrefslogtreecommitdiffstats
path: root/lib/Tooling/Refactoring/Extract
diff options
context:
space:
mode:
Diffstat (limited to 'lib/Tooling/Refactoring/Extract')
-rw-r--r--lib/Tooling/Refactoring/Extract/Extract.cpp199
-rw-r--r--lib/Tooling/Refactoring/Extract/SourceExtraction.cpp112
-rw-r--r--lib/Tooling/Refactoring/Extract/SourceExtraction.h52
3 files changed, 363 insertions, 0 deletions
diff --git a/lib/Tooling/Refactoring/Extract/Extract.cpp b/lib/Tooling/Refactoring/Extract/Extract.cpp
new file mode 100644
index 0000000000..b0847a7400
--- /dev/null
+++ b/lib/Tooling/Refactoring/Extract/Extract.cpp
@@ -0,0 +1,199 @@
+//===--- Extract.cpp - Clang refactoring library --------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// \brief Implements the "extract" refactoring that can pull code into
+/// new functions, methods or declare new variables.
+///
+//===----------------------------------------------------------------------===//
+
+#include "clang/Tooling/Refactoring/Extract/Extract.h"
+#include "SourceExtraction.h"
+#include "clang/AST/ASTContext.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/ExprObjC.h"
+#include "clang/Rewrite/Core/Rewriter.h"
+
+namespace clang {
+namespace tooling {
+
+namespace {
+
+/// Returns true if \c E is a simple literal or a reference expression that
+/// should not be extracted.
+bool isSimpleExpression(const Expr *E) {
+ if (!E)
+ return false;
+ switch (E->IgnoreParenCasts()->getStmtClass()) {
+ case Stmt::DeclRefExprClass:
+ case Stmt::PredefinedExprClass:
+ case Stmt::IntegerLiteralClass:
+ case Stmt::FloatingLiteralClass:
+ case Stmt::ImaginaryLiteralClass:
+ case Stmt::CharacterLiteralClass:
+ case Stmt::StringLiteralClass:
+ return true;
+ default:
+ return false;
+ }
+}
+
+SourceLocation computeFunctionExtractionLocation(const Decl *D) {
+ if (isa<CXXMethodDecl>(D)) {
+ // Code from method that is defined in class body should be extracted to a
+ // function defined just before the class.
+ while (const auto *RD = dyn_cast<CXXRecordDecl>(D->getLexicalDeclContext()))
+ D = RD;
+ }
+ return D->getLocStart();
+}
+
+} // end anonymous namespace
+
+const RefactoringDescriptor &ExtractFunction::describe() {
+ static const RefactoringDescriptor Descriptor = {
+ "extract-function",
+ "Extract Function",
+ "(WIP action; use with caution!) Extracts code into a new function",
+ };
+ return Descriptor;
+}
+
+Expected<ExtractFunction>
+ExtractFunction::initiate(RefactoringRuleContext &Context,
+ CodeRangeASTSelection Code,
+ Optional<std::string> DeclName) {
+ // We would like to extract code out of functions/methods/blocks.
+ // Prohibit extraction from things like global variable / field
+ // initializers and other top-level expressions.
+ if (!Code.isInFunctionLikeBodyOfCode())
+ return Context.createDiagnosticError(
+ diag::err_refactor_code_outside_of_function);
+
+ if (Code.size() == 1) {
+ // Avoid extraction of simple literals and references.
+ if (isSimpleExpression(dyn_cast<Expr>(Code[0])))
+ return Context.createDiagnosticError(
+ diag::err_refactor_extract_simple_expression);
+
+ // Property setters can't be extracted.
+ if (const auto *PRE = dyn_cast<ObjCPropertyRefExpr>(Code[0])) {
+ if (!PRE->isMessagingGetter())
+ return Context.createDiagnosticError(
+ diag::err_refactor_extract_prohibited_expression);
+ }
+ }
+
+ return ExtractFunction(std::move(Code), DeclName);
+}
+
+// FIXME: Support C++ method extraction.
+// FIXME: Support Objective-C method extraction.
+Expected<AtomicChanges>
+ExtractFunction::createSourceReplacements(RefactoringRuleContext &Context) {
+ const Decl *ParentDecl = Code.getFunctionLikeNearestParent();
+ assert(ParentDecl && "missing parent");
+
+ // Compute the source range of the code that should be extracted.
+ SourceRange ExtractedRange(Code[0]->getLocStart(),
+ Code[Code.size() - 1]->getLocEnd());
+ // FIXME (Alex L): Add code that accounts for macro locations.
+
+ ASTContext &AST = Context.getASTContext();
+ SourceManager &SM = AST.getSourceManager();
+ const LangOptions &LangOpts = AST.getLangOpts();
+ Rewriter ExtractedCodeRewriter(SM, LangOpts);
+
+ // FIXME: Capture used variables.
+
+ // Compute the return type.
+ QualType ReturnType = AST.VoidTy;
+ // FIXME (Alex L): Account for the return statement in extracted code.
+ // FIXME (Alex L): Check for lexical expression instead.
+ bool IsExpr = Code.size() == 1 && isa<Expr>(Code[0]);
+ if (IsExpr) {
+ // FIXME (Alex L): Get a more user-friendly type if needed.
+ ReturnType = cast<Expr>(Code[0])->getType();
+ }
+
+ // FIXME: Rewrite the extracted code performing any required adjustments.
+
+ // FIXME: Capture any field if necessary (method -> function extraction).
+
+ // FIXME: Sort captured variables by name.
+
+ // FIXME: Capture 'this' / 'self' if necessary.
+
+ // FIXME: Compute the actual parameter types.
+
+ // Compute the location of the extracted declaration.
+ SourceLocation ExtractedDeclLocation =
+ computeFunctionExtractionLocation(ParentDecl);
+ // FIXME: Adjust the location to account for any preceding comments.
+
+ // FIXME: Adjust with PP awareness like in Sema to get correct 'bool'
+ // treatment.
+ PrintingPolicy PP = AST.getPrintingPolicy();
+ // FIXME: PP.UseStdFunctionForLambda = true;
+ PP.SuppressStrongLifetime = true;
+ PP.SuppressLifetimeQualifiers = true;
+ PP.SuppressUnwrittenScope = true;
+
+ ExtractionSemicolonPolicy Semicolons = ExtractionSemicolonPolicy::compute(
+ Code[Code.size() - 1], ExtractedRange, SM, LangOpts);
+ AtomicChange Change(SM, ExtractedDeclLocation);
+ // Create the replacement for the extracted declaration.
+ {
+ std::string ExtractedCode;
+ llvm::raw_string_ostream OS(ExtractedCode);
+ // FIXME: Use 'inline' in header.
+ OS << "static ";
+ ReturnType.print(OS, PP, DeclName);
+ OS << '(';
+ // FIXME: Arguments.
+ OS << ')';
+
+ // Function body.
+ OS << " {\n";
+ if (IsExpr && !ReturnType->isVoidType())
+ OS << "return ";
+ OS << ExtractedCodeRewriter.getRewrittenText(ExtractedRange);
+ if (Semicolons.isNeededInExtractedFunction())
+ OS << ';';
+ OS << "\n}\n\n";
+ auto Err = Change.insert(SM, ExtractedDeclLocation, OS.str());
+ if (Err)
+ return std::move(Err);
+ }
+
+ // Create the replacement for the call to the extracted declaration.
+ {
+ std::string ReplacedCode;
+ llvm::raw_string_ostream OS(ReplacedCode);
+
+ OS << DeclName << '(';
+ // FIXME: Forward arguments.
+ OS << ')';
+ if (Semicolons.isNeededInOriginalFunction())
+ OS << ';';
+
+ auto Err = Change.replace(
+ SM, CharSourceRange::getTokenRange(ExtractedRange), OS.str());
+ if (Err)
+ return std::move(Err);
+ }
+
+ // FIXME: Add support for assocciated symbol location to AtomicChange to mark
+ // the ranges of the name of the extracted declaration.
+ return AtomicChanges{std::move(Change)};
+}
+
+} // end namespace tooling
+} // end namespace clang
diff --git a/lib/Tooling/Refactoring/Extract/SourceExtraction.cpp b/lib/Tooling/Refactoring/Extract/SourceExtraction.cpp
new file mode 100644
index 0000000000..7fd8cc2d3c
--- /dev/null
+++ b/lib/Tooling/Refactoring/Extract/SourceExtraction.cpp
@@ -0,0 +1,112 @@
+//===--- SourceExtraction.cpp - Clang refactoring library -----------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "SourceExtraction.h"
+#include "clang/AST/Stmt.h"
+#include "clang/AST/StmtCXX.h"
+#include "clang/AST/StmtObjC.h"
+#include "clang/Basic/SourceManager.h"
+#include "clang/Lex/Lexer.h"
+
+using namespace clang;
+
+namespace {
+
+/// Returns true if the token at the given location is a semicolon.
+bool isSemicolonAtLocation(SourceLocation TokenLoc, const SourceManager &SM,
+ const LangOptions &LangOpts) {
+ return Lexer::getSourceText(
+ CharSourceRange::getTokenRange(TokenLoc, TokenLoc), SM,
+ LangOpts) == ";";
+}
+
+/// Returns true if there should be a semicolon after the given statement.
+bool isSemicolonRequiredAfter(const Stmt *S) {
+ if (isa<CompoundStmt>(S))
+ return false;
+ if (const auto *If = dyn_cast<IfStmt>(S))
+ return isSemicolonRequiredAfter(If->getElse() ? If->getElse()
+ : If->getThen());
+ if (const auto *While = dyn_cast<WhileStmt>(S))
+ return isSemicolonRequiredAfter(While->getBody());
+ if (const auto *For = dyn_cast<ForStmt>(S))
+ return isSemicolonRequiredAfter(For->getBody());
+ if (const auto *CXXFor = dyn_cast<CXXForRangeStmt>(S))
+ return isSemicolonRequiredAfter(CXXFor->getBody());
+ if (const auto *ObjCFor = dyn_cast<ObjCForCollectionStmt>(S))
+ return isSemicolonRequiredAfter(ObjCFor->getBody());
+ switch (S->getStmtClass()) {
+ case Stmt::SwitchStmtClass:
+ case Stmt::CXXTryStmtClass:
+ case Stmt::ObjCAtSynchronizedStmtClass:
+ case Stmt::ObjCAutoreleasePoolStmtClass:
+ case Stmt::ObjCAtTryStmtClass:
+ return false;
+ default:
+ return true;
+ }
+}
+
+/// Returns true if the two source locations are on the same line.
+bool areOnSameLine(SourceLocation Loc1, SourceLocation Loc2,
+ const SourceManager &SM) {
+ return !Loc1.isMacroID() && !Loc2.isMacroID() &&
+ SM.getSpellingLineNumber(Loc1) == SM.getSpellingLineNumber(Loc2);
+}
+
+} // end anonymous namespace
+
+namespace clang {
+namespace tooling {
+
+ExtractionSemicolonPolicy
+ExtractionSemicolonPolicy::compute(const Stmt *S, SourceRange &ExtractedRange,
+ const SourceManager &SM,
+ const LangOptions &LangOpts) {
+ auto neededInExtractedFunction = []() {
+ return ExtractionSemicolonPolicy(true, false);
+ };
+ auto neededInOriginalFunction = []() {
+ return ExtractionSemicolonPolicy(false, true);
+ };
+
+ /// The extracted expression should be terminated with a ';'. The call to
+ /// the extracted function will replace this expression, so it won't need
+ /// a terminating ';'.
+ if (isa<Expr>(S))
+ return neededInExtractedFunction();
+
+ /// Some statements don't need to be terminated with ';'. The call to the
+ /// extracted function will be a standalone statement, so it should be
+ /// terminated with a ';'.
+ bool NeedsSemi = isSemicolonRequiredAfter(S);
+ if (!NeedsSemi)
+ return neededInOriginalFunction();
+
+ /// Some statements might end at ';'. The extraction will move that ';', so
+ /// the call to the extracted function should be terminated with a ';'.
+ SourceLocation End = ExtractedRange.getEnd();
+ if (isSemicolonAtLocation(End, SM, LangOpts))
+ return neededInOriginalFunction();
+
+ /// Other statements should generally have a trailing ';'. We can try to find
+ /// it and move it together it with the extracted code.
+ Optional<Token> NextToken = Lexer::findNextToken(End, SM, LangOpts);
+ if (NextToken && NextToken->is(tok::semi) &&
+ areOnSameLine(NextToken->getLocation(), End, SM)) {
+ ExtractedRange.setEnd(NextToken->getLocation());
+ return neededInOriginalFunction();
+ }
+
+ /// Otherwise insert semicolons in both places.
+ return ExtractionSemicolonPolicy(true, true);
+}
+
+} // end namespace tooling
+} // end namespace clang
diff --git a/lib/Tooling/Refactoring/Extract/SourceExtraction.h b/lib/Tooling/Refactoring/Extract/SourceExtraction.h
new file mode 100644
index 0000000000..4b4bd8b477
--- /dev/null
+++ b/lib/Tooling/Refactoring/Extract/SourceExtraction.h
@@ -0,0 +1,52 @@
+//===--- SourceExtraction.cpp - Clang refactoring library -----------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_LIB_TOOLING_REFACTORING_EXTRACT_SOURCE_EXTRACTION_H
+#define LLVM_CLANG_LIB_TOOLING_REFACTORING_EXTRACT_SOURCE_EXTRACTION_H
+
+#include "clang/Basic/LLVM.h"
+
+namespace clang {
+
+class LangOptions;
+class SourceManager;
+class SourceRange;
+class Stmt;
+
+namespace tooling {
+
+/// Determines which semicolons should be inserted during extraction.
+class ExtractionSemicolonPolicy {
+public:
+ bool isNeededInExtractedFunction() const {
+ return IsNeededInExtractedFunction;
+ }
+
+ bool isNeededInOriginalFunction() const { return IsNeededInOriginalFunction; }
+
+ /// Returns the semicolon insertion policy that is needed for extraction of
+ /// the given statement from the given source range.
+ static ExtractionSemicolonPolicy compute(const Stmt *S,
+ SourceRange &ExtractedRange,
+ const SourceManager &SM,
+ const LangOptions &LangOpts);
+
+private:
+ ExtractionSemicolonPolicy(bool IsNeededInExtractedFunction,
+ bool IsNeededInOriginalFunction)
+ : IsNeededInExtractedFunction(IsNeededInExtractedFunction),
+ IsNeededInOriginalFunction(IsNeededInOriginalFunction) {}
+ bool IsNeededInExtractedFunction;
+ bool IsNeededInOriginalFunction;
+};
+
+} // end namespace tooling
+} // end namespace clang
+
+#endif // LLVM_CLANG_LIB_TOOLING_REFACTORING_EXTRACT_SOURCE_EXTRACTION_H